One key element is likely psychological trauma. It's often the starting point for her multiple personalities. Another could be some external influence that exacerbated the situation.
Crazy Jane is a complex and interesting character. Her origin story likely involves some sort of trauma or extraordinary event that led to her multiple personalities. Each personality might have its own powers and backstories, which together make up the enigma that is Crazy Jane.
One idea could be exploring Crazy Jane's different personalities and how they interact with each other in a new and unexpected situation, like a day out in a big city. Another could be a fanfic where she has to team up with other superheroes and her personalities cause some comical or challenging moments during the mission.
Definitely Cliff Steele. His robotic nature and his own internal struggles could contrast well with Crazy Jane's multiple personalities. Another good one is Rita Farr. Her insecurities and her ability to change form could lead to some interesting interactions with Jane.
Natalie Nelson in 'natalie nelson the school story' is likely the central figure. She could be a girl who has a unique personality. Maybe she's really smart or really creative. Since it's a school story, she's most likely a student who experiences all kinds of things in school, like making friends, having rivalries, and learning important life lessons.
It's hard to say. We don't have much direct evidence or reports indicating if Natalie Portman is into comics. Maybe she does in her private time, but it's not something that's been widely disclosed.